On Alcohol or spirituous Liquors. 275 
barytes occasioned in it a slight precipitate. It was also easy 
afterwards, by means of the blue vegetable colours, to discover in 
it the presence of the alkali set free by the subtraction of the 
sulphuric acid united to the ponderous earth. 
By a second rectification over the same calcined salt, we may 
have alcohol at 42 degrees, but vain will be the attempt to give it 
a higher degree of levity by other distillations : this liquor differs _ 
only from spirit of wine prepared without intermedium, in so far 
as it contains a slight quantity of sulphate of soda in solution. 
By the calcined Acetate of Potash. 
This method, which was lately suggested by an eminent che- 
mist of Paris, succeeds beyond every other: pure alcohol distil- 
led in the vapour-bath over this salt acquires more than 46 de- 
grees (at the temperature of 10+0 Reaumur) ; but having ex- 
amined this liquor, I soon perceived that it was no longer spirit’ 
of wine: it differed from it, Ist, by having a very pungent 
smell, something like the tincture of salt of tartar of the shops. 
2d, It had an acrid soapy and bitterish taste. 3d, It changed 
into green the aqueous tincture of the petals of violets, &c. 
It is therefore very evident that the alcohol obtained by this 
process is of a great levity, but the properties peculiar to this fluid 
remove it from the rank of pure spirit of wine, and make it a 
new liquid. 
From the above short detail, and the facts resulting from ex- 
periments carefully made on pure alcohol from 38 to 40 degrees, 
extracted from the various mucoso-saccharine substances which 
have undergone the spirituous fermentation, it appears demon- 
strated that all the six saline substances above cited, have an ac- 
tion more or less direct, not only on the last portions of water 
which adhere very strongly to the alcohol, but also upon the con- 
stituent parts of this same fluid: hence we must conclude, that 
all these intermedia do not exactly procure a spirit of wine de- 
phlegmated to the maximum, and preserving all the physical and 
chemical properties which ought to render it saleable and useful. 
It has also been proposed to subtract the water from alcohol 
at 36 degrees, by distilling it in the vapour-bath with a weak 
dose of sulphuric acid: for instance =1,th of its weight. I have 
observed that so long as spirit of wine does not exceed 38 de- 
grees, it preserves by this rectification the properties which cha- 
racterize it; but if we add a new portion of acid to the latter, 
the product then acquires, with its specific lightness, a fragrant 
odour slightly ethereated: this already announces an alteration 
in the elementary principles of the spirituous fluid. 
The common alum of commerce calcined, considering the 
great quantity of humidity which it loses during its exposure to fire, 
$2 . seems 
